TY - RPRT T1 - Natural resource condition assessment: John Muir National Historical Site Y1 - 2014 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Jantz, P. A. PB - National Park Service UR - https://irma.nps.gov/App/Reference/Profile/2218894 ER - TY - RPRT T1 - Natural resource condition assessment: Pinnacles National Monument Y1 - 2013 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Jantz, P. A. PB - National Park Service CY - Fort Collins, Colorado SN - Natural Resource Report NPS/PINN/NRR-2013/709 ER - TY - RPRT T1 - Natural resource condition assessment: Santa Monica Mountains National Recreation Area Y1 - 2013 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Jantz, P. A. PB - National Park Service CY - Fort Collins, Colorado SN - Natural Resource Report NPS/SAMO/NRR-2013/715 ER - TY - JOUR T1 - Siting solar energy development to minimize biological impacts JF - Renewable Energy Y1 - 2013 A1 - Stoms, D. M. A1 - Dashiell, S. L. A1 - Davis, F. W. KW - ecological condition KW - GIS KW - mitigation hierarchy KW - multicriteria analysis KW - siting criteria KW - utility-scale solar energy AB -

After solar and other renewable energy developers select generally suitable sites for exploration, they frequently encounter conflict over biodiversity conservation values that were not factored into the initial suitability rating methods. This paper presents a spatial multicriteria analysis method for modeling risk of conflict with biological resources and applies the model in the California deserts where such conflicts are rapidly rising. The premise of the model is that the least conflict will occur on sites that are the most ecologically degraded with low conservation value and that would engender low offsite impacts when connecting to existing transmission infrastructure. Model results suggest sufficient compatible land exists in flat, non-urban areas to meet state solar energy targets of 18-26 GW of installed capacity in the California deserts for 2050. The model is a promising tool to fill the gap between site suitability analysis for renewable energy and regional biodiversity conservation planning to identify areas where rapid impact assessment and permitting will generate the least regrets.

VL - 57 ER - TY - ABST T1 - Mapping compatibility to minimize biodiversity impacts of solar energy development in the California Deserts Y1 - 2011 A1 - Stoms, D. M. A1 - Dashiell, S. L. A1 - Davis, F. W. PB - Biogeography Lab, University of California Santa Barbara ER - TY - JOUR T1 - The power of information for targeting cost-effective conservation investments in multifunctional farmlands JF - Environmental Modelling & Software Y1 - 2011 A1 - Stoms, D. M. A1 - Kreitler, J. A1 - Davis, F. W. KW - spatial targeting farmland preservation marginal value benefits costs Great Central Valley California threats additionality ecosystem services urban growth management AB - Decisions about which places to conserve are based upon the geographic heterogeneity of three types of information: public goods or benefits, their vulnerability to threats, and the costs to avert those threats. The choice of public goods depends on the mission of the conservation organization (e.g., biodiversity, open space, cultural values, or farmland). For spatial targeting of conservation at the regional scale, practitioners must estimate the values of these types of information. The quality of the estimations will vary by the primary data used, the assumptions made, and the practitioner's technical ability to analyze complex data. This paper contributes to the growing literature by presenting a systematic evaluation of effect of the quality of the estimation on the cost-effectiveness of the set of sites selected for conservation based upon those estimates. The specific case study targets farmland for preservation from urban development in California's Central Valley where a new land trust was recently established to purchase conservation easements. In one analysis, we compared the cost-effectiveness of farmland benefits using our most sophisticated estimation procedures to those that ignored costs and/or potential loss (i.e., assumed they were equal among sites). Excluding information about the potential loss of resources caused only a slight decrease in cost-effectiveness. On the other hand, ignoring cost information was extremely inefficient. The second analysis compared the performance of the sophisticated estimated to increasingly simpler estimates, such as those representative of the methods used by many American farmland preservation programs. The simplification of the estimates caused a 5- to 20-fold decline in the benefits that could be retained for a given budget. To make more cost-effective targeting strategies accessible to farmland preservation programs, we recommend that researchers develop new spatial targeting tools to overcome obstacles in data processing. VL - 26 ER - TY - JOUR T1 - Change in urban land use and associated attributes in the Upper San Francisco Estuary, 1990-2006 JF - San Francisco Estuarine & Watershed Science Y1 - 2010 A1 - Stoms, D. M. KW - urban growth geographic information systems GIS hydrodynamic subregions housing density road-stream crossings impervious cover AB - Land use is an ultimate driver of many of the stressors on the Upper San Francisco Estuary, but the magnitude and pattern of land use change has not been analyzed. I attempted to fill this knowledge gap through a screening-level risk assessment. I compared urban land use within hydrodynamic subregions in 1990, 2000, and 2006. Ancillary data were then used to quantify secondary measures such as impervious cover, housing density, road density and road crossings. Despite the rapid growth of the Bay Area, Sacramento, and Stockton metropolitan areas, the percentage of urban area and rates of change in the subregions are generally low to moderate when compared to other estuaries in the United States. The spatial data sets used in this analysis have been posted online to a public repository to be used by other researchers addressing topics such as fate and transport of contaminants. VL - 8 N1 - submitted 7/5/09 ER - TY - JOUR T1 - Coupling GIS and LCA for biodiversity assessments of land use: Part 1 Inventory modeling JF - International Journal of Life Cycle Assessment Y1 - 2010 A1 - Geyer, R. A1 - Stoms, D. M. A1 - Lindner, J. P. A1 - Davis, F. W. A1 - Wittstock, B. KW - Biodiversity habitats land use geographic information systems GIS spatially-explicit inventory modeling bioethanol biofuel LCA life cycle assessment crop production model spatially-explicit LCI consequential LCA geographic variability AB - Purpose: Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially-explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California. Methods: GIS modeling was used to generate crop production scenarios for corn and sugar beets that met a range of ethanol production targets. The selected study area was a four county region in the southern San Joaquin Valley of California, USA. The resulting land use maps were translated into maps of habitat types. From these maps, vectors were created that contained the total areas for each habitat type in the study region. These habitat composition vec-tors are treated as elementary input flows and used to calculate different biodiversity impact indicators in a second paper (Geyer et al. this volume). Results and discussion: Ten ethanol production scenarios were developed with GIS modeling. Current land use is added as baseline scenario. The parcels selected for corn and sugar beet production were generally in different loca-tions. Moreover, corn and sugar beets are classified as different habitat types. Consequently the scenarios differed in both the habitat types converted and in the habitat types expanded. Importantly, land use increased non-linearly with increasing ethanol production targets. The GIS modeling for this study used spatial data that are commonly available in most developed countries and only required functions that are provided in virtually any commercial or open-source GIS software package. Conclusions: This study has demonstrated that GIS-based inventory modeling of land use allows important refine-ments in LCA theory and practice. Using GIS, land use can be modeled as a geospatial and non-linear function of output. For each spatially explicit process, land use can be expressed within the conventional structure of LCA methodology as a set of elementary input flows of habitat types. VL - 15 ER - TY - JOUR T1 - Coupling GIS and LCA for biodiversity assessments of land use: Part 2 Impact assessment JF - International Journal of Life Cycle Assessment Y1 - 2010 A1 - Geyer, R. A1 - Lindner, J. P. A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Wittstock, B. KW - GIS-based inventory modeling land use habitats hemeroby species richness abundance evenness biodiversity impacts bioethanol Biodiversity geographic variability life cycle impact assessment bioethanol biofuel LCA AB - Purpose: Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially-explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California. Methods: In Part 2 of this paper series, four biodiversity impact indicators are presented and discussed, which use the inventory data on habitat composition and sizes from the GIS-based inventory modeling in Part 1 (Geyer et al. this volume). The concepts used to develop characterization models are hemeroby, species richness, species abun-dance, and species evenness. The biodiversity assessments based on species richness, abundance, and evenness use a habitat-species suitability matrix, which relates 443 terrestrial vertebrate species native to California to the 29 habi-tat types that occur in the study area. Results and discussion: The structural similarities and differences of all four characterization models are discussed in some detail. Characterization factors and indicator results are calculated for each of the four characterization models and the 11 different land use scenarios from Part 1 of this paper series. For the sugar beet production scenar-ios, the indicator results are in fairly good agreement. For the corn production scenarios, however, they come to fun-damentally different results. The overall approach of using GIS-based inventory data on land use together with in-formation on habitat-species relationships is not only feasible, but also grounded in ecological science and well con-nected with existing LCIA efforts. Conclusions: Excluding biodiversity impacts from land use significantly limits the scope of LCA. Accounting for land use in inventory modeling is dramatically enhanced if LCA is coupled with GIS. The resulting inventory data is a sound basis for biodiversity impact assessments, in particular if coupled with information on habitat-species rela-tionships. However, much more case studies and structural analysis of indicators is required, together with an evaluation framework that enables comparisons and ranking of indicators. VL - 15 ER - TY - JOUR T1 - Implementation of State Wildlife Action Plans: Conservation impacts, challenges and enabling mechanisms JF - Gap Analysis Bulletin Y1 - 2010 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Scott, J. M. KW - SWAP state wildlife action plans distributed graduate seminar gap analysis GAP VL - 17 ER - TY - JOUR T1 - Socioeconomic patterns of American farmland preservation funded by the Farm and Ranch Lands Protection Program JF - Journal of Conservation Planning Y1 - 2010 A1 - Stoms, D. M. A1 - DeAngelo, G. KW - agricultural conservation easements KW - Farm and Ranchland Protection Program KW - FRPP KW - land trusts KW - local food movement KW - sprawl KW - urban growth AB - Since 1996 the federal Farm and Ranchland Protection Program (FRPP) has supported local programs to preserve their farmland by providing matching funds to "eligible cooperating entities." This paper analyzes where those funds have been distributed and then asks what kinds of communities choose to preserve farmland (i.e., become eligible cooperating entities) and which do not? And how widespread is farmland preservation likely to become in the near future? To answer these questions we compiled historical county-level spatial data on demographics, economics, agricultural, and GIS-based growth pattern statistics to characterize counties that have implemented farmland preservation programs as represented in FRPP allocations. Statistical models determined the probability that a county has received funding and predicted the level of funding. Applying the regression coefficients to contemporary data then forecast the level of funding expected in the coming decade if sufficient funds are available; that is, where current socioeconomic conditions now match the historic conditions that favored preservation at the initiation of the FRPP. The most significant variables of FRPP activity in counties were a combination of socioeconomic factors for the county as a whole (per capita income, population growth in the preceding decade), agricultural factors (area of farmland, direct sales of products to individuals in dollars), and a synthetic GIS-based index of sprawl. Although FRPP cannot distribute funds based on predicted "demand", prospective farmland preservationists may be inspired to act if they see that their county has characteristics similar to those that have already succeeded in meeting FRPP eligibility criteria. VL - 6 UR - http://www.journalconsplanning.org/2010/JCP_v6_2_Stoms.pdf ER - TY - JOUR T1 - Designing the Ark, 21st-century style JF - Ecology Y1 - 2009 A1 - Stoms, D. M. KW - conservation area network reserve selection biodiversity surrogates representativeness persistence VL - 90 N1 - margules and sarkar, systematic conservation planning ER - TY - CHAP T1 - GIS and Decision Making: The Gap Analysis Program (GAP) T2 - Manual of Geographic Information Systems Y1 - 2009 A1 - Kramer, L. A1 - McKerrow, A. J. A1 - Pearlstine, L. G. A1 - Mazzotti, F. J. A1 - Stoms, D. M. A1 - Maxwell, J. ED - Madden, Marguerite KW - gap analysis GIS reserve selection farmland preservation JF - Manual of Geographic Information Systems PB - American Society for Photogrammetry and Remote Sensing CY - Bethesda, MD ER - TY - JOUR T1 - Spatial patterns of endemic plants in California JF - Natural Areas Journal Y1 - 2009 A1 - Thorne, J. H. A1 - Viers, J. H. A1 - Price, J. A1 - Stoms, D. M. KW - endemism KW - flora KW - geodatabase KW - hotspots KW - Plant biogeography KW - range size AB - California endemic vascular plant range patterns were quantified using a flora-based geodatabase technique that combined species presence in geographic areas and elevation band occupation. Resulting species range maps were summarized by 228 geographic areas. Over 60% of the endemic species range size distributions were found to have range sizes less than 10,000 km2. The largest endemic taxon range was 275,749 km2, or 67% of the state. California endemic plants had different distribution patterns depending on the criteria used to portray them. California's Central Coast Ranges, Sierra Nevada foothills, high elevation Sierra Nevada Mountains, Channel Islands, San Jacinto Mountains, Napa and Lake Counties, Inyo Mountains, sections of the Mojave Desert, and San Bernardino Mountains were all identified as areas with unique endemic plant attributes. We compared endemic species richness between map units in zones that have similar topography and climate, and found that area only weakly correlated with species richness, suggesting other factors have stronger influence on endemism in continental California. The findings have implications for developing conservation plans that target endemic species. In particular, we identify areas of the state, previously de-emphasized, that deserve greater recognition based on the characteristics of their restricted endemic plants. Range distribution estimates produced from floral keys made digital proved effective in this study, an inexpensive approach that could be implemented in other regions of the world for which floras have been published. VL - 29 UR - http://www.naturalarea.org/journaltoc.aspx?p=154 ER - TY - JOUR T1 - Strategic targeting of agricultural conservation easements as a growth management tool JF - Land Use Policy Y1 - 2009 A1 - Stoms, D. M. A1 - Jantz, P. A. A1 - Davis, F. W. A1 - DeAngelo, G. KW - strategic conservation planning spatial targeting GIS smart growth farmland preservation urban growth boundaries AB - Public and private programs have preserved an estimated 730,000 ha of agricultural land in the United States, by acquiring agricultural conservation easements (ACEs) that retire a property's development rights. ACEs could be a potent tool for smart growth if strategically targeted. This paper attempts to quantify measures of strategic farmland preservation as guidance for planners. Evaluating the placement of 318 ACEs in the San Francisco Bay of California produced mixed results. Preservation and development of agricultural land were both in conformance with general plans. In contrast, we found little evidence of ACEs being used on a regional scale to reinforce urban growth boundaries. Recently ACEs have begun to coalesce into larger blocks of preserved agricultural land, but not near the rural-urban fringe. We encourage planners to consider farmland preservation as a politically-acceptable tool to complement traditional planning tools to minimize low-density sprawl. VL - 26 N1 - 10.1016/j.landusepol.2009.02.004 ER - TY - JOUR T1 - Efficient conservation in a utility-maximization framework JF - Ecology and Society Y1 - 2006 A1 - Davis, F. W. A1 - Costello, C. J. A1 - Stoms, D. M. KW - Biodiversity conservation planning California cost-effectiveness scenario marginal conservation value retention AB - Systematic planning for biodiversity conservation is being conducted at scales ranging from global to national and regional. The prevailing planning paradigm is to identify the minimal land allocations needed to reach specified conservation targets or for maximizing the amount of conservation accomplished under an area or budget constraint. We propose a more general formulation for setting conservation priorities that involves goal setting, assessing the current conservation system, and estimating the contribution of a site to overall utility. Under this new formulation of the problem, the value of a site depends on resource quality, threats to resource quality, and costs. We allocate available conservation funds to sites to maximize the overall utility of the regional conservation system, expressed in terms of the biodiversity remaining at the end of the planning period. The planning approach is designed to support collaborative processes and negotiation among competing interest groups. We demonstrate these ideas with a case study of the Sierra Nevada Bioregion of California. VL - 11 ER - TY - JOUR T1 - Human impacts, plant invasion, and imperiled plant species in California JF - Ecological Applications Y1 - 2006 A1 - Seabloom, E. W. A1 - Williams, J. W. A1 - Slayback, D. A1 - Stoms, D. M. A1 - Viers, J. H. A1 - Dobson, A. P. KW - California KW - dispersal KW - exotic plants KW - extinction KW - global biodiversity hotspot KW - habitat loss KW - invasive species KW - rare species KW - species richness KW - structural equation models AB - Invasive species are one of the fastest growing conservation problems. These species homogenize the world’s flora and fauna, threaten rare and endemic species, and impose large economic costs. Here, we examine the distribution of 834 of the more than 1000 exotic plant taxa that have become established in California, USA. Total species richness increases with productivity; however, the exotic flora is richest in low-lying coastal sites that harbor large numbers of imperiled species, while native diversity is highest in areas with high mean elevation. Weedy and invasive exotics are more tightly linked to the distribution of imperiled species than the overall pool of exotic species. Structural equation modeling suggests that while human activities, such as urbanization and agriculture, facilitate the initial invasion by exotic plants, exotics spread ahead of the front of human development into areas with high numbers of threatened native plants. The range sizes of exotic taxa are an order of magnitude smaller than for comparable native taxa. The current small range size of exotic species implies that California has a significant ‘‘invasion debt’’ that will be paid as exotic plants expand their range and spread throughout the state. VL - 16 UR - http://www.esajournals.org/esaonline/?request=get-abstract&issn=1051-0761&volume=016&issue=04&page=1338 ER - TY - JOUR T1 - Prioritizing farmland preservation cost-effectively for multiple objectives JF - Journal of Soil and Water Conservation Y1 - 2006 A1 - Machado, E. A. A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Kreitler, J. KW - amenities KW - Bay Delta bioregion KW - California Legacy Project KW - conservation planning KW - cost-effectiveness KW - decision analysis KW - ecosystem services KW - farmland preservation KW - GIS KW - marginal value KW - public preferences KW - social welfare KW - urban growth boundary KW - urban growth management KW - utility AB - American society derives many benefits from farmland and is often willing to pay to preserve it from urbanization. We present an innovative framework to support farmland preservation programs in prioritizing conservation investments. The framework considers the full range of social benefits of farmland and improves the application of decision analysis methods to the process. Key factors for ranking farms are: 1) social objectives and priorities 2) how much farmland value is expected to be lost to development if not preserved, 3) how much farmland value is already secured in the agricultural region; and 4) how much it will cost to secure the farm's benefits. The framework can be applied strategically over an entire region or to rank a set of applications from landowners. We demonstrate our framework using three criteria in the Bay Area/Delta bioregion of California, USA. VL - 61 UR - ://000242001800007 ER - TY - JOUR T1 - Viable reserve networks arise from individual landholder responses to conservation incentives JF - Ecology and Society Y1 - 2006 A1 - Chomitz, K. M. A1 - Fonseca, G. A. B. Da A1 - Alger, K. A1 - Stoms, D. M. A1 - Honzák, M. A1 - Landau, E. Charlotte A1 - Thomas, T. S. A1 - Thomas, W. Wayt A1 - Davis, F. KW - Bahia biodiversity conservation conservation planning economic instruments land use AB - Conservation in densely-settled biodiversity hotspots areas often requires setting up reserve networks that maintain sufficient contiguous habitat to support viable species populations. Because it is difficult to secure landholder compliance with an tightly constrained reserve network design, attention has shifted to voluntary incentive mechanisms, such as purchase of conservation easements by reverse auction or through a fixed-price offer. These mechanisms carry potential advantages of transparency, simplicity, and low cost. But uncoordinated individual response to these incentives has been assumed to be incompatible with conservation goals of viability (which depends on contiguous habitat) and biodiversity representation. We model such incentives for southern Bahia in the Brazilian Atlantic Forest, one of the biologically richest and most threatened global biodiversity hotspots. Here, forest cover is spatially autocorrelated and associated with depressed land values, a situation that may be characteristic of long-settled areas with forests fragmented by agriculture. We find that in this situation, a voluntary incentive system can yield a reserve network characterized by large, viable patches of contiguous forest, and representation of subregions with distinct vegetation types and biotic assemblages – without explicit planning for those outcomes. VL - 11 ER - TY - JOUR T1 - Anthropogenic impacts upon plant species richness and NPP in California JF - Ecology Letters Y1 - 2005 A1 - Williams, J. W. A1 - Seabloom, E. W. A1 - Slayback, D. A1 - Stoms, D. M. A1 - Viers, J. H. KW - California KW - human impacts KW - Land cover change KW - net primary productivity KW - species richness KW - structural equation models AB - We assess the importance of anthropogenic land-use, altered productivity, and species invasions for observed productivity-richness relationships in California. To this end, we model net primary productivity (NPP) c. 1750 AD and at present (1982-1999) and map native and exotic vascular plant richness for 230 subecoregions. NPP has increased up to 105% in semi-arid areas and decreased up to 48% in coastal urbanized areas. Exotic invasions have increased local species diversity up to 15%. Human activities have reinforced historical gradients in species richness but reduced the spatial heterogeneity of NPP. Structural equation modelling suggests that, prior to European settlement, NPP and richness were primarily controlled by precipitation and other abiotic variables, with NPP mediating richness. Abiotic variables remain the strongest predictors of present NPP and richness, but intermodel comparisons indicate a significant anthropogenic impact upon statewide distributions of NPP and richness. Exotic and native species each positively correlate to NPP after controlling for other variables, which may help explain recent reports of positively associated native and exotic richness. VL - 8 UR - ://000226491200001 ER - TY - JOUR T1 - Choosing surrogates for biodiversity conservation in complex planning environments JF - Journal of Conservation Planning Y1 - 2005 A1 - Stoms, D. M. A1 - Comer, P. J. A1 - Crist, P. J. A1 - Grossman, D. H. KW - coarse-filter KW - conservation planning KW - fine-filter KW - Napa County KW - reserve selection KW - sensitivity analysis KW - Sites KW - surrogates AB - The coarse filter/fine filter hypothesis suggests that by conserving high-quality examples of all ecological systems along with imperiled species and communities, we could protect the majority of native biodiversity. Given the cost of data collection, conservation planners might wonder how large this set of elements must be. We conducted an analysis of the sensitivity of selecting a set of reserves to the choice of surrogates in Napa County, California, USA. The study evaluated the extent to which conservation goals for the coarse/fine-filter elements were met by surrogates and whether the same general locations were being selected. Napa County represents a data-rich setting, whereas the test surrogates portrayed a range of circumstances where less data are available. A worst (data-poor) case, based only on landscape condition with no biological data, was tested to identify the value of improved information. Our results suggest that in complex planning environments, there are no simple shortcuts in collecting data. None of the surrogate sets was particularly effective at meeting all the goals for the full set of baseline elements. There was also relatively low spatial congruence between the test solutions and the baseline. However, we did find that all combinations of surrogates provided some degree of protection in notional reserves, suggesting that in less complex planning problems, simpler surrogates can serve a useful function. Studies like this will help planners gauge how much effort it is prudent to spend in compiling spatial data relative to the risks and irreplaceability to native biodiversity. VL - 1 UR - http://www.journalconsplanning.org/2005/volume1/issue1/stoms/manuscript.pdf ER - TY - CHAP T1 - A framework for setting land conservation priorities in the Sierra Nevada T2 - Proceedings of the Sierra Nevada Science Symposium Y1 - 2004 A1 - Davis, F. W. A1 - Costello, C. J. A1 - Stoms, D. M. A1 - Machado, E. A. A1 - Metz, J. ED - Murphy, Dennis D. ED - Stine, Peter A. KW - California Legacy Project KW - conservation planning KW - decision support system KW - GIS KW - marginal value KW - prioritization AB - The California Legacy Project (CLP) mission is "to enable the State and its partners in conservation to develop and implement a strategic and inclusive approach to conserving and restoring California's lands and natural resources." Here we provide a brief overview of a framework that we developed to serve the dual purpose of helping decision makers to evaluate current opportunities (e.g., current proposal applications for State conservation funds) and to help planners develop longer term conservation strategies that highlight general areas, species and communities for more focused analysis and collaborative planning. Site prioritization depends on the resources the site contains, the threat to those resources, and the conservation cost of mitigating that threat. We illustrate our framework using relatively coarse, readily available data for the Sierra Nevada Bioregion. Preliminary results suggest that many of the private lands of the region contribute important conservation value for terrestrial biodiversity. However, inter-site disparities in degree of threat and in conservation costs make the conservation "bang for buck" especially high in a smaller number of sites. JF - Proceedings of the Sierra Nevada Science Symposium PB - Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture CY - Albany, CA VL - General Technical Report PSW-GTR-193 UR - http://www.fs.fed.us/psw/publications/documents/psw_gtr193/psw_gtr193_5_4_Davis_and_others.pdf N1 - presented at Sierra Nevada Science Symposium 2002 October 7-10; Kings Beach, CA. ER - TY - CHAP T1 - A framework for setting land conservation priorities in the Sierra Nevada T2 - Proceedings of the Sierra Nevada Science Symposium Y1 - 2004 A1 - Davis, F. W. A1 - Costello, C. J. A1 - Stoms, D. M. A1 - Machado, E. A. A1 - Metz, J. ED - Murphy, Dennis D. ED - Stine, Peter A. KW - California Legacy Project marginal value conservation planning prioritization decision support system GIS AB - The California Legacy Project (CLP) mission is "to enable the State and its partners in conservation to develop and implement a strategic and inclusive approach to conserving and restoring California's lands and natural resources." Here we provide a brief overview of a framework that we developed to serve the dual purpose of helping decision makers to evaluate current opportunities (e.g., current proposal applications for State conservation funds) and to help planners develop longer term conservation strategies that highlight general areas, species and communities for more focused analysis and collaborative planning. Site prioritization depends on the resources the site contains, the threat to those resources, and the conservation cost of mitigating that threat. We illustrate our framework using relatively coarse, readily available data for the Sierra Nevada Bioregion. Preliminary results suggest that many of the private lands of the region contribute important conservation value for terrestrial biodiversity. However, inter-site disparities in degree of threat and in conservation costs make the conservation "bang for buck" especially high in a smaller number of sites. JF - Proceedings of the Sierra Nevada Science Symposium PB - Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture CY - Albany, CA VL - General Technical Report PSW-GTR-193 N1 - presented at Sierra Nevada Science Symposium 2002 October 7-10; Kings Beach, CA. ER - TY - JOUR T1 - A framework to extend gap analysis to multi-objective conservation planning JF - Gap Analysis Program Annual Bulletin Y1 - 2004 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Costello, C. J. A1 - Machado, E. A. A1 - Metz, J. VL - 12 UR - http://www.gap.uidaho.edu/Bulletins/12/A%20Framework%20to%20Extend%20Gap%20Analysis.htm ER - TY - ABST T1 - A framework for setting land conservation priorities using multi-criteria scoring and an optimal fund allocation strategy Y1 - 2003 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Costello, C. J. A1 - Machado, E. A. A1 - Metz, J. A1 - Gerrard, R. A1 - Andelman, S. A1 - Regan, H. A1 - Church, R. KW - marginal value conservation planning cost-effectiveness GIS Sierra Nevada California Legacy Project AB - The California Legacy Project (CLP) mission is "to enable the State and its partners in conservation to develop and implement a strategic and inclusive approach to conserving and restoring California's lands and natural resources." In Spring 2001 The Resources Agency of California contracted with the National Center for Ecological Analysis and Synthesis at UC Santa Barbara to convene a working group to help bring systematic conservation planning theory and methods to bear on the design and implementation of CLP. The framework described in this report is one of the products from that working group. The framework is intended to serve the dual purpose of helping decision makers to evaluate current opportunities (e.g., current proposal applications for State conservation funds) and to help planners develop longer term conservation strategies that highlight general areas, species and communities for more focused analysis and collaborative planning. We do not present a plan or "blueprint" for future conservation activities. Instead, we offer an analytical, data-driven planning process that could be applied to ongoing conservation assessments and evaluations by State conservation planning staff and collaborating organizations over the State or regions of the State. We organize the planning framework based on a hierarchy of conservation goals and objectives, each of which is further elaborated in terms of specific objectives, criteria, and sources of evidence. At the highest level we distinguish three categories of conservation goals: Resource Production Capacity, Natural Capital, and Public Open Space. Under Natural Capital we distinguish terrestrial biodiversity from wetland and aquatic biodiversity. This report focuses on terrestrial biodiversity. The framework applies GIS technology to map conservation value and investment priorities based on available spatial data, derived indices and simple algebraic functions. A planning region is divided into sites and each site is scored in terms of its marginal conservation value, that is, the incremental value added to the current system of conservation lands by making the next conservation investment in that site. Site prioritization depends on the resources the site contains, the threat to those resources, and the conservation cost of mitigating that threat. The strategic objective is to allocate conservation funds among a set of candidate sites such that there is the greatest possible resource value remaining at the end of the planning period. We present a measure of ecological condition based on land use, land cover, roads, housing density and forest structure. The condition index is mapped for 2000 A.D. and 2040 A.D. (based on projected patterns of housing development) and the difference between the two is applied as a measure of threat to biodiversity. We then present formal measures for five different values that places can have for conserving terrestrial biodiversity: 1) hotspots of rare threatened and endangered species, 2) areas supporting vulnerable habitat types, 3) unique landscapes, 4) wildlands for area dependent species, and 5) areas to expand the size of existing reserves. We apply the framework to prioritize new conservation investments on private lands in the Sierra Bioregion. Our purpose is to demonstrate the end-to-end use of the framework and attention should be focused on the process, not the actual products. We first use existing, readily available data to map resource values and threats to produce maps of marginal conservation value without consideration of site cost. Spatial patterns in site value differ considerably among the five conservation criteria. We then use a crude estimate of land prices and allocate a hypothetical budget of $44 million to 50 sites scattered across the region. The framework can also be applied to other conservation concerns such as aquatic biodiversity, production lands, public open space, cultural resources and recreational opportunities. In a separate report we demonstrate its application for cropland conservation in the Bay Delta Bioregion. Our initial experiences in applying the framework to terrestrial biodiversity and cropland are very encouraging, but testing and refinement of the indices and value functions models are still needed and are currently underway. PB - National Center for Ecological Analysis and Synthesis ER - TY - ABST T1 - Linking GIS and reserve selection algorithms: Towards a geospatial data model Y1 - 2003 A1 - Stoms, D. M. KW - data model reserve selection object-oriented conservation planning AB - Most reserve selection algorithms used in research or conservation practice are only loosely coupled with geographic information system technology. This paper argues that formalizing a core geospatial data model would benefit algorithm developers, researchers, and practitioners through standardized data management and ease of database development with any reserve selection algorithm. PB - Biogeography Lab, Bren School of Environmental Science and Management, University of California Santa Barbara ER - TY - RPRT T1 - Linking GIS and reserve selection algorithms: Towards a geospatial data model Y1 - 2003 A1 - Stoms, D. M. KW - conservation planning KW - data model KW - object-oriented KW - reserve selection AB - Most reserve selection algorithms used in research or conservation practice are only loosely coupled with geographic information system technology. This paper argues that formalizing a core geospatial data model would benefit algorithm developers, researchers, and practitioners through standardized data management and ease of database development with any reserve selection algorithm. PB - Biogeography Lab, Bren School of Environmental Science and Management, University of California Santa Barbara UR - http://www.biogeog.ucsb.edu/pubs/Technical%20Reports/Reserve_Selection_Data_Model.pdf ER - TY - ABST T1 - A systematic framework for prioritizing farmland preservation Y1 - 2003 A1 - Machado, E. A. A1 - Stoms, D. M. A1 - Davis, F. W. KW - marginal value conservation planning cost-effectiveness GIS Bay Delta bioregion farmland preservation California Legacy Project AB - The California Legacy Project (CLP) mission is "to enable the state and its partners in conservation to develop and implement a strategic and inclusive approach to conserving and restoring California's lands and natural resources." In 2001 The Resources Agency of California contracted with the National Center for Ecological Analysis and Synthesis at UC Santa Barbara to convene a working group to help bring systematic conservation planning theory and methods to bear on the design and implementation of CLP. The conservation planning framework for farmland described in this report for is one of the products from that working group. The framework is intended to serve the dual purpose of helping decision makers to evaluate current opportunities (e.g., current proposal applications for State conservation funds) and to help planners develop longer term conservation strategies that highlight areas for more focused analysis and collaborative planning. We do not present a plan or "blueprint" for future conservation activities. Instead, we offer an analytical, data-driven planning process that could be applied to ongoing conservation assessments and evaluations by State conservation planning staff and collaborating organizations over the State or regions of the State. We organize the planning framework based on a hierarchy of conservation goals and objectives, each of which is further elaborated in terms of specific objectives, criteria, and sources of evidence. For farmland preservation, we summarize these goals as retaining farmlands: 1) with the greatest sustained production capacity, 2) that provide high amenity values (e.g., habitat, open space, floodplain management, and scenic values), and 3) whose location reduces the risk of urban sprawl. The framework applies GIS technology to map farmland conservation value and investment priorities based on available spatial data, derived indices and simple algebraic functions. A planning region is divided into sites, and each site is scored in terms of its marginal conservation value, that is, the incremental value added to the current system of conservation lands by making the next conservation investment in that site. Site prioritization depends on the farmland resources the site contains, the threat to those resources, and the conservation cost of mitigating that threat. The strategic objective is to allocate conservation funds among a set of candidate sites such that there is the greatest possible farmland value remaining at the end of the planning period. We demonstrate the framework for preservation of farmlands in the Bay Area/Delta Bioregion. Because the criteria for measuring objectives 2 and 3 require spatial and nonspatial data that are not readily available statewide or even for a bioregion, we only develop and demonstrate the framework for objective 1. Existing data are used to map resource values and threats to arrive at maps of marginal conservation value without consideration of site cost. We use a crude estimate of the cost of conservation easements to demonstrate how the framework could then be used to prioritize conservation investments subject to a fixed budget. PB - National Center for Ecological Analysis and Synthesis ER - TY - RPRT T1 - A systematic framework for prioritizing farmland preservation Y1 - 2003 A1 - Machado, E. A. A1 - Stoms, D. M. A1 - Davis, F. W. KW - Bay Delta bioregion KW - California Legacy Project KW - conservation planning KW - cost-effectiveness KW - farmland preservation KW - GIS KW - marginal value AB - The California Legacy Project (CLP) mission is "to enable the state and its partners in conservation to develop and implement a strategic and inclusive approach to conserving and restoring California's lands and natural resources." In 2001 The Resources Agency of California contracted with the National Center for Ecological Analysis and Synthesis at UC Santa Barbara to convene a working group to help bring systematic conservation planning theory and methods to bear on the design and implementation of CLP. The conservation planning framework for farmland described in this report for is one of the products from that working group. The framework is intended to serve the dual purpose of helping decision makers to evaluate current opportunities (e.g., current proposal applications for State conservation funds) and to help planners develop longer term conservation strategies that highlight areas for more focused analysis and collaborative planning. We do not present a plan or "blueprint" for future conservation activities. Instead, we offer an analytical, data-driven planning process that could be applied to ongoing conservation assessments and evaluations by State conservation planning staff and collaborating organizations over the State or regions of the State. We organize the planning framework based on a hierarchy of conservation goals and objectives, each of which is further elaborated in terms of specific objectives, criteria, and sources of evidence. For farmland preservation, we summarize these goals as retaining farmlands: 1) with the greatest sustained production capacity, 2) that provide high amenity values (e.g., habitat, open space, floodplain management, and scenic values), and 3) whose location reduces the risk of urban sprawl. The framework applies GIS technology to map farmland conservation value and investment priorities based on available spatial data, derived indices and simple algebraic functions. A planning region is divided into sites, and each site is scored in terms of its marginal conservation value, that is, the incremental value added to the current system of conservation lands by making the next conservation investment in that site. Site prioritization depends on the farmland resources the site contains, the threat to those resources, and the conservation cost of mitigating that threat. The strategic objective is to allocate conservation funds among a set of candidate sites such that there is the greatest possible farmland value remaining at the end of the planning period. We demonstrate the framework for preservation of farmlands in the Bay Area/Delta Bioregion. Because the criteria for measuring objectives 2 and 3 require spatial and nonspatial data that are not readily available statewide or even for a bioregion, we only develop and demonstrate the framework for objective 1. Existing data are used to map resource values and threats to arrive at maps of marginal conservation value without consideration of site cost. We use a crude estimate of the cost of conservation easements to demonstrate how the framework could then be used to prioritize conservation investments subject to a fixed budget. PB - National Center for Ecological Analysis and Synthesis CY - Santa Barbara UR - http://www.nceas.ucsb.edu/nceas-web/projects/4040/Farmland_framework_report.pdf ER - TY - RPRT T1 - Economic Instruments for Habitat Conservation Y1 - 2002 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Church, R. L. A1 - Gerrard, R. A. PB - University of California, Santa Barbara CY - Santa Barbara UR - http://www.biogeog.ucsb.edu/projects/wb/wbrpt2002.pdf ER - TY - ABST T1 - Economic Instruments for Habitat Conservation Y1 - 2002 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Church, R. L. A1 - Gerrard, R. A. PB - University of California, Santa Barbara ER - TY - JOUR T1 - Extinction rates under nonrandom patterns of habitat loss JF - Proceedings of the National Academy of Science of the United States of America Y1 - 2002 A1 - Seabloom, E. W. A1 - Dobson, A. P. A1 - Stoms, D. M. AB - Most models that examine the effects of habitat conversion on species extinctions assume that habitat conversion occurs at random. This assumption allows predictions about extinction rates based on the speciesarea relationship. We show that the spatially aggregated nature of habitat conversion introduces a significant bias that may lead species-loss rates to exceed those predicted by speciesarea curves. Correlations between human activity and major compositional gradients, or species richness, also alter predicted species extinction rates. We illustrate the consequences of nonrandom patterns of habitat conversion by using a data set that combines the distribution of native vascular plants with human activity patterns in California. VL - 99 ER - TY - CONF T1 - Integrating biodiversity into land use planning: Research contributions T2 - American Planning Association National Planning Conference Y1 - 2001 A1 - Stoms, D. M. AB - Preservation of biodiversity is one of the most contentious environmental issues in the United States. Researchers have made progress in improving our understanding of the impacts of development but this has not led to much improvement in planning tools. This talk will offer a conceptual framework for addressing biodiversity-related planning questions. A model for selecting new biological reserves will be described, both to illustrate some of the lessons learned and future directions needed to incorporate biodiversity management into the larger arena of land use planning. The key to progress is better integration among scientists from different disciplines. JF - American Planning Association National Planning Conference CY - New Orleans UR - http://www.asu.edu/caed/proceedings01/STOMS/stoms.htm ER - TY - CONF T1 - Spatial decision support systems for wildlife conservation planning T2 - International Seminar on the Wildlife Habitat Suitability Mapping and Management Y1 - 2001 A1 - Davis, F. W. A1 - Stoms, D. M. JF - International Seminar on the Wildlife Habitat Suitability Mapping and Management CY - Seoul, Korea ER - TY - JOUR T1 - GAP management status and regional indicators of threats to biodiversity JF - Landscape Ecology Y1 - 2000 A1 - Stoms, D. M. KW - roadedness biodiversity ecological indicators California gap analysis land use projected human population growth road density index zoning AB - Conservation assessment requires quantitative criteria for evaluating the relative degree of threat faced by species or ecological communities. Identifying appropriate criteria for communities is complicated because the species inhabiting them can have many different responses to land uses and other forms of environmental stress. The Gap Analysis Program (GAP) uses summary data on the proportion of the community that is protected as an estimate of its vulnerability. Management status from a gap analysis of California was compared with three ecological indicators (permitted land uses, human population growth, and the spatial extent of road effects) that more directly represent impacts on biodiversity. The classification of management status appears to provide a crude first approximation of these three indicators. Public and private lands that are not formally protected were susceptible to extensive land use conversion or resource extraction in both rural and urban settings. Some plant community types are more susceptible to future infringement by human population increases that were not well predicted by management status alone. Other community types are heavily roaded despite being moderately well protected. It is suggested that indicators such as future growth and current road effects could complement status in rating the potential vulnerability of plant communities and setting conservation priorities. The choice of indicators will depend on the threatening processes in a given region and the availability of spatial data to map or model them. VL - 15 ER - TY - CHAP T1 - Owning up to our responsibilities: Who owns lands important for biodiversity? T2 - Precious Heritage: The Status of Biodiversity in the United States Y1 - 2000 A1 - Groves, C. R. A1 - Kutner, L. S. A1 - Stoms, D. M. A1 - Muray, M. P. A1 - Scott, J. M. A1 - Schafale, M. A1 - Weakley, A. S. A1 - Pressey, R. L. ED - Stein, B. A. ED - Kutner, L. S. ED - Adams, J. S. JF - Precious Heritage: The Status of Biodiversity in the United States PB - Oxford University Press CY - Oxford ER - TY - CHAP T1 - Owning up to our responsibilities: Who owns lands important for biodiversity? T2 - Precious Heritage: The Status of Biodiversity in the United States Y1 - 2000 A1 - Groves, C. R. A1 - Kutner, L. S. A1 - Stoms, D. M. A1 - Muray, M. P. A1 - Scott, J. M. A1 - Schafale, M. A1 - Weakley, A. S. A1 - Pressey, R. L. ED - Stein, B. A. ED - Kutner, L. S. ED - Adams, J. S. JF - Precious Heritage: The Status of Biodiversity in the United States PB - Oxford University Press CY - Oxford UR - http://www.abi.org/pheritage-es.htm ER - TY - JOUR T1 - Potential NDVI as a baseline for monitoring ecosystem functioning JF - International Journal of Remote Sensing Y1 - 2000 A1 - Stoms, D. M. A1 - Hargrove, W. W. KW - AVHRR KW - California KW - GAP KW - managed areas KW - NDVI KW - net primary production KW - NPP KW - Oregon KW - regression tree analysis KW - time integrated NDVI KW - Washington AB - Baseline data are needed to determine the overall magnitude and direction of change in ecosystem functioning. This letter presents an approach to estimate potential NDVI from environmental variables and training data of actual NDVI in nature reserves. Patterns of deviations of actual NDVI from the baseline generally correspond with land-use types in the western United States. VL - 21 UR - ://000084681200014 ER - TY - JOUR T1 - Systematic reserve selection in the USA: An example from the Columbia Plateau ecoregion JF - Parks Y1 - 1999 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Andelman, S. KW - BMAS biodiversity management areas reserve selection The Nature Conservancy TNC Columbia Plateau Geography of Hope coarse-filter fine-filter expert opinion AB - We describe a systematic conservation planning approach for identifying a set of areas that meet specified goals for biotic representation while balancing the dual objectives of efficiency (minimum area) and site suitability. The approach was applied by The Nature Conservancy (TNC) to a regional planning exercise in the Columbia Plateau ecoregion of the northwestern United States. The exercise required integrating data on species, plant communities, land ownership and other socioeconomic factors, and combined expert opinion with computer-aided site selection modeling. The set of selected areas satisfied TNC's requirements and now serves as a blueprint for ongoing conservation efforts in the region. Strengths of the approach include its explicitness, flexibility, and consideration of both biological goals and socioeconomic concerns. However, the current site selection model requires fairly sophisticated computing hardware and software, which limits its portability and use by non-specialists. We are currently working to improve model portability and to add new functionality for site prioritization and species viability. VL - 9 ER - TY - ABST T1 - Acquisition and Evaluation of Data Sets for Comparative Assessment of Risk to Biodiversity on a Continental Scale: Threats to Biodiversity Y1 - 1998 A1 - Stoms, D. M. A1 - Kuhn, W. A. A1 - Davis, F. W. A1 - Final Report to the Environmental Protection Agency, C. A. pp KW - anthropogenic effects KW - biodiversity KW - NDVI KW - potential NDVI KW - rare species KW - species richness KW - stressors KW - West Cosat Transect PB - University of California, Santa Barbara N1 - [] ER - TY - RPRT T1 - Acquisition and Evaluation of Data Sets for Comparative Assessment of Risk to Biodiversity on a Continental Scale: Threats to Biodiversity Y1 - 1998 A1 - Stoms, D. M. A1 - Kuhn, W. A. A1 - Davis, F. W. A1 - Final Report to the Environmental Protection Agency, C. A. pp KW - stressors, anthropogenic effects, biodiversity, NDVI, potential NDVI, species richness, rare species, West Cosat Transect PB - University of California, Santa Barbara UR - http://www.biogeog.ucsb.edu/projects/epa/epa_rpt.html N1 - [] ER - TY - ABST T1 - The California Gap Analysis Project-Final Report Y1 - 1998 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Hollander, A. D. A1 - Thomas, K. A. A1 - Stine, P. A. A1 - Odion, D. A1 - Borchert, M. I. A1 - Thorne, J. H. A1 - Gray, M. V. A1 - Walker, R. E. A1 - Warner, K. A1 - Graae, J. PB - University of California, Santa Barbara ER - TY - JOUR T1 - Gap analysis of the vegetation of the Intermountain Semi-Desert Ecoregion JF - Great Basin Naturalist Y1 - 1998 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Driese, K. L. A1 - Cassidy, K. M. A1 - Murray, M. P. KW - actual vegetation KW - alliance KW - gap analysis KW - Intermountain Semi-Desert ecoregion KW - National Vegetation Classification Standards KW - NVCS AB - A conservation gap analysis was conducted for the Intermountain Semi-Desert ecoregion to assess the representation of land-cover types within areas managed primarily for biodiversity objectives. Mapped distributions of plant communities were summarized by land management status categories. The total amount of land permanently protected in the ecoregion is less than 4% and most types that are characteristic of the region have less than 10%. Of 48 land-cover types, 20 were found to be particularly vulnerable to potential loss or degradation, because of low level of representation in biodiversity management areas and the impact of expected land use activities. The gap analysis data and findings will be useful in providing a regional perspective in project impact assessment and future conservation planning within this ecoregion. VL - 58 UR - ://000074765200001 ER - TY - JOUR T1 - Map-guided classification of regional land-cover with multi-temporal AVHRR data JF - Photogrammetric Engineering and Remote Sensing Y1 - 1998 A1 - Stoms, D. M. A1 - Bueno, M. J. A1 - Davis, F. W. A1 - Cassidy, K. M. A1 - Driese, K. L. A1 - Kagan, J. S. KW - accuracy assessment KW - AVHRR KW - gap analysis KW - Intermountain Semidesert ecoregion KW - map-guided classification KW - National Vegetation Classification Standards KW - NVCS KW - remote sensing AB - Cartographers often need to use information in existing land-cover maps when compiling regional or global maps, but there are no standardized techniques for using such data effectively. An iterative, map-guided classification approach was developed to compile a spatially and thematically consistent, seamless land-cover map of the entire Intermountain Semi-Desert ecoregion from a set of semi-independent subregional maps derived by various methods. A multi-temporal dataset derived from AVHRR data was classified using the subregional maps as training data. The resulting regional map attempted to meet the guidelines of the proposed National Vegetation Classification Standards for classification at the alliance level. The approach generally improved the spatial properties of the regional mapping, while maintaining the thematic detail of the source maps. The methods described may be useful in many situations where mapped information exists but is incomplete, compiled by different methods, or is based on inconsistent classification systems. VL - 64 UR - ://000075109200012 ER - TY - JOUR T1 - A systematic process for selecting representative Research Natural Areas JF - Natural Areas Journal Y1 - 1998 A1 - Stoms, D. M. A1 - Borchert, M. I. A1 - Moritz, M. A. A1 - Davis, F. W. A1 - Church, R. L. KW - reserve selection algorithm weighted-benefits maximal covering location problem Los Padres National Forest research natural areas AB -

Prioritizing sites as potential Research Natural Areas to represent a set of target vegetation types is a complex planning problem in which competing objectives must be satisfied simultaneously, including suitability and efficiency. We describe a general process for identifying and siting potential Research Natural Areas that is based on a systematic description of vegetation and environmental variation in the region, analysis of patterns of vegetation ownership and management, and optimal site selection based both on vegetational and environmental criteria. The approach is demonstrated with an application to siting Research Natural Areas to represent Mixed Evergreen Forest types on Los Padres National Forest in the central coast of California. We envision this process as a preliminary step that would precede more detailed ground survey and administrative review procedures as currently practiced. It could also be adapted to similar programs of regional conservation planning.

VL - 18 UR - http://fiesta.bren.ucsb.edu/~fd/Pubs/stoms_et_al_RNA98.pdf ER - TY - RPRT T1 - Preserve Selection Modeling in the Columbia Plateau Y1 - 1997 A1 - Stoms, D. M. A1 - Okin, W. J. A1 - Davis, F. W. PB - University of California, Santa Barbara CY - Santa Barbara UR - http://www.biogeog.ucsb.edu/projects/tnc/tnc_report.html ER - TY - ABST T1 - Preserve Selection Modeling in the Columbia Plateau Y1 - 1997 A1 - Stoms, D. M. A1 - Okin, W. J. A1 - Davis, F. W. PB - University of California, Santa Barbara ER - TY - CONF T1 - A proposed protocol for identifying potential Research Natural Areas with Gap Analysis data T2 - 17th Annual ESRI User Conference Y1 - 1997 A1 - Moritz, M. A1 - Stoms, D. M. A1 - Borchert, M. I. A1 - Davis, F. W. KW - research natural areas, reserve selection algorithm, Los Padres National Forest AB - In this paper we propose a protocol for identifying and evaluating candidate sites for the U. S. National Forest's Research Natural Area (RNA) program. The approach is explicit and repeatable and consists of the five following steps: 1) Vegetation Target Type Identification, 2) Quantification of Environmental Variation, 3) Calculation of Site Suitability, 4) Site Selection, and 5) Ground Truth. We also describe a prototype case study using this approach for Mixed Evergreen Forest in Los Padres National Forest in central coastal California. This case study demonstrates the usefulness of Gap Analysis data and GIS-based procedures in conjunction with applications outside GIS, such as vegetation classification and optimization programs. Results indicate that there are often complex trade-offs between efficiency (i.e, covering the most types with the least sites) and suitability (i.e., choosing the most ecologically appropriate sites) of solutions, even in a simple case such as the one described here. JF - 17th Annual ESRI User Conference PB - ESRI CY - San Diego UR - http://www.esri.com/base/common/userconf/proc97/PROC97/TO150/PAP145/P145.HTM ER - TY - JOUR T1 - Selecting conservation reserves using species covering models: Adapting the ARC/INFO GIS JF - Transactions in GIS Y1 - 1997 A1 - Gerrard, R. A. A1 - Church, R. L. A1 - Stoms, D. M. A1 - Davis, F. W. AB - Conflicts between human development of the landscape and conservation of biodiversity will continue to grow. Given this reality, there have been a number of attempts to model the optimal selection of conservation reserve sites such that maximum biodiversity protection can be attained within a limited budget for land acquisition. Here we adapt the Location-Allocation module of ARC/INFO to solve the problem of representing, or covering, as many species as possible in a fixed number of selected reserve sites. Resident ARC/INFO solution routines are applied to an innovative logical network that converts the problem of optimal reserve selection into a problem of optimal facility placement, which the Location-Allocation module can recognize and solve. Use of this unique logical network structure as input to ARC/INFO's internal solvers makes possible, compared to previous methods, a much tighter integration of spatial optimization tools with mapping and database tools, all of which are internal to the GIS and accessed via a menu-driven interface. The main advantage is that users of public domain data (such as the U.S. Gap Analysis data) can conduct their own explorations of possible reserve systems without having to acquire and master optimization packages and reformat model output data for GIS display and post-analysis of solutions. Our sample application uses species data from southwestern California. We also present a second major form of species covering model grounded in the same logical network. This enhanced model accommodates weighting of species by their conservation importance, thus allowing reserve systems to be designed around the portection of the most threatened or vulnerable biota. VL - 2 ER - TY - ABST T1 - A Spatial Modeling and Decision Support System for Conservation of Biological Diversity Y1 - 1997 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Hollander, A. D. A1 - Bueno, M. J. A1 - Church, R. L. A1 - Okin, W. J. A1 - Gerrard, R. A. PB - University of California, Santa Barbara ER - TY - JOUR T1 - Viewing geometry of AVHRR image composites derived using multiple criteria JF - Photogrammetric Engineering and Remote Sensing Y1 - 1997 A1 - Stoms, D. M. A1 - Bueno, M. J. A1 - Davis, F. W. KW - AVHRR KW - cloud removal KW - compositing KW - NDVI KW - Normalized Difference Vegetation Index KW - satellite zenith angle AB - The U. S. Geological Survey currently generates composites of AVHRR imagery based on a single objective--maximizing the Normalized Difference Vegetation Index--as a means of reducing cloud contamination. Our research supports the findings of others that in some cases, NDVI is maximized at the expense of optimal viewing geometry; that is, satellite zenith angles are often further off-nadir than necessary to ensure cloud-free viewing. We explore various compositing methods by systematically varying weights on NDVI, satellite zenith angle, and maximum apparent temperature. A test composite of California from September 1990 appears to be superior to the maximum NDVI and maximum apparent temperature composites in several respects. First, the satellite zenith angle distribution is more closely clustered about nadir, which minimizes atmospheric path length, spatial distortion, and bidirectional reflectance effects. Second, neighboring pixels are more frequently selected with similar viewing geometry and atmospheric conditions. VL - 63 UR - ://A1997XC40700004 ER - TY - CHAP T1 - Hierarchical representation of species distributions for biological survey and monitoring T2 - GIS and Environmental Modeling: Progress and Research Issues Y1 - 1996 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Hollander, A. D. ED - Goodchild, M. F. ED - Steyaert, L. T. ED - Parks, B. O. KW - data hypercube, orange-throated whiptail, GIS modeling AB - Spatial and temporal axes of domain, grain, and sampling intensity can serve as a framework to discuss opportunities for integrating spatial biodiversity data into richer, more complex representations of species distributions. This conceptual framework also highlights many of the problems in integrating data of different spatial, temporal and thematic properties. A recent analysis of the distribution of the orange-throated whiptail lizard in southern California is reviewed as an example of integration of datasets. Comparison of representations resulting from different data sources makes biases evident, highlights areas of inadequate sampling, and can lead to new inferences about habitat relationships through convergence of evidence. Improvements in the technology needed to facilitate better integration of distribution models with GIS in the areas of data entry, linkages to tools outside traditional GIS functionality, and new GIS tools to integrate existing datasets are discussed. JF - GIS and Environmental Modeling: Progress and Research Issues PB - GIS World Books CY - Fort Collins, Colorado ER - TY - CHAP T1 - Hierarchical representation of species distributions for biological survey and monitoring T2 - GIS and Environmental Modeling: Progress and Research Issues Y1 - 1996 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Hollander, A. D. ED - Goodchild, M. F. ED - Steyaert, L. T. ED - Parks, B. O. KW - data hypercube KW - GIS modeling KW - orange-throated whiptail AB - Spatial and temporal axes of domain, grain, and sampling intensity can serve as a framework to discuss opportunities for integrating spatial biodiversity data into richer, more complex representations of species distributions. This conceptual framework also highlights many of the problems in integrating data of different spatial, temporal and thematic properties. A recent analysis of the distribution of the orange-throated whiptail lizard in southern California is reviewed as an example of integration of datasets. Comparison of representations resulting from different data sources makes biases evident, highlights areas of inadequate sampling, and can lead to new inferences about habitat relationships through convergence of evidence. Improvements in the technology needed to facilitate better integration of distribution models with GIS in the areas of data entry, linkages to tools outside traditional GIS functionality, and new GIS tools to integrate existing datasets are discussed. JF - GIS and Environmental Modeling: Progress and Research Issues PB - GIS World Books CY - Fort Collins, Colorado ER - TY - CONF T1 - Planning management activities to protect biodiversity with GIS and an integrated optimization model T2 - Third International Conference/Workshop on Integrating GIS and Environmental Modeling Y1 - 1996 A1 - Church, R. L. A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Okin, B. J. KW - BMAS model, Sierra Nevada, GIS model integration AB - We present the details of a general spatial model that was developed for the selection of biodiversity management areas in the Sierra Nevada Region. This model is loosely integrated with a GIS system. The basic modeling approach begins by first identifying those plant communities that are vulnerable due to land use activities in current management plans. The level of vulnerability is assessed for each element of interest on a spatial basis using ARC/INFO. The planning problem involves selecting an efficient set of watersheds for biodiversity management through specially developed heuristics and the Optimization Subroutine Library of IBM. Results of this approach are given for the northern region of the Sierra Nevada of California. The BMAS model represents a significant advance in GIS-based conservation planning, both in sophistication of the algorithms used and in the integration of cultural and land use data with biological data. JF - Third International Conference/Workshop on Integrating GIS and Environmental Modeling PB - National Center for Geographic Information and Analysis CY - Santa Fe, New Mexico UR - http://www.ncgia.ucsb.edu/conf/SANTA_FE_CD-ROM/sf_papers/church_richard/my_paper.html ER - TY - JOUR T1 - Reserve selection as a maximal covering location problem JF - Biological Conservation Y1 - 1996 A1 - Church, R. L. A1 - Stoms, D. M. A1 - Davis, F. W. KW - reserve selection conservation planning optimization AB - Many alternative approaches have been proposed for setting conservation priorities from a database of species (or communities) by site. We present a model based on the premise that reserve selection or site prioritization can be structured as a classic covering problem commonly used in many location problems. Specifically, we utilize a form of the maximal covering location model to identify sets of sites which represent the maximum possible representation of specific species. An example application is given for vertebrate data of Southwestern California, which is then compared to an iterative solution process used in previous studies. It is shown that the maximal covering model can quickly meet or exceed iterative models in terms of the coverage objective and automatically satisfies a complementarity objective. Refinements to the basic model are also proposed to address additional objectives such as irreplaceability and flexibility. VL - 76 ER - TY - CHAP T1 - Selecting biodiversity management areas T2 - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Church, R. L. A1 - Okin, W. J. A1 - Johnson, K. N. KW - biodiversity management area, reserve selection, BMAS model, representation, Sierra Nevada, California AB - Here we present and evaluate a conservation strategy whose objective is to represent all native plant communities in areas where the primary management goal is to sustain native biodiversity. We refer to these areas as Biodiversity Management Areas (BMAs), which we define as specially designated public or private lands with an active ecosystem management plan in operation whose purpose is to contribute to regional maintenance of native genetic, species and community levels of biodiversity, and the processes that maintain that biodiversity. Our purpose in this chapter is to explore opportunities for siting BMAs in the Sierra Nevada region. The strategic goal is to design a BMA system that represents all major Sierran plant community types, which we use as a coarse surrogate for ecosystems and their component species. We consider a community type to be represented if some pre-defined fraction of its mapped distribution occurs in one or more BMAs. We use a multi-objective computer model to allocate a minimum of new land to BMA status subject to the constraints that all community types must be represented, and that the new BMA areas should be located in areas of highest suitability for BMA status. Our purpose in this exercise is not to identify the optimal sites for a Sierran BMA system; instead it is to measure some of the likely dimensions of plausible, alternative BMA systems for the Sierra Nevada and to develop a rationale that would guide others in formulating such a system. Thus we examine a wide range of possible BMA systems based on different assumptions, constraints, target levels for representation, and priorities. If one ignores current land ownership and management designations and sets out to represent plant communities in a BMA system based on Calwater planning watersheds (which average roughly 10,000 acres in size), an efficient BMA system requires land in direct proportion to the target level, at least over the range of target levels examined in this study. In other words, it takes roughly 10% of the region to meet a 10% goal, and 25% of the region to meet a 25% goal. The pattern of selected watersheds is very different from the current distribution of parks and wilderness areas, which are concentrated at middle and high elevations in the central and southern portion of the range. Public lands alone are insufficient to create a BMA system that adequately represents all plant community types of the Sierra Nevada. Many of the foothill community types occur almost exclusively on private lands. Terrestrial vertebrates are reasonably well represented in a BMA system selected for plant communities. A BMA system selected for vertebrates alone, however, has little overlap with the one for plant communities. Areas selected by the BMAS model show only a modest amount of overlap with areas selected by other SNEP working groups as focal areas for conserving aquatic biodiversity or late successional/old growth forests. However, the BMAS model can be formulated to favor these areas with little loss of efficiency, especially in the northern Sierra. JF - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options PB - University of California, Centers for Water and Wildlands Resources CY - Davis, California UR - http://ceres.ca.gov/snep/pubs/web/PDF/VII_C58.PDF ER - TY - CHAP T1 - Selecting biodiversity management areas T2 - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Church, R. L. A1 - Okin, W. J. A1 - Johnson, K. N. KW - biodiversity management area KW - BMAS model KW - California KW - representation KW - reserve selection KW - Sierra Nevada AB - Here we present and evaluate a conservation strategy whose objective is to represent all native plant communities in areas where the primary management goal is to sustain native biodiversity. We refer to these areas as Biodiversity Management Areas (BMAs), which we define as specially designated public or private lands with an active ecosystem management plan in operation whose purpose is to contribute to regional maintenance of native genetic, species and community levels of biodiversity, and the processes that maintain that biodiversity. Our purpose in this chapter is to explore opportunities for siting BMAs in the Sierra Nevada region. The strategic goal is to design a BMA system that represents all major Sierran plant community types, which we use as a coarse surrogate for ecosystems and their component species. We consider a community type to be represented if some pre-defined fraction of its mapped distribution occurs in one or more BMAs. We use a multi-objective computer model to allocate a minimum of new land to BMA status subject to the constraints that all community types must be represented, and that the new BMA areas should be located in areas of highest suitability for BMA status. Our purpose in this exercise is not to identify the optimal sites for a Sierran BMA system; instead it is to measure some of the likely dimensions of plausible, alternative BMA systems for the Sierra Nevada and to develop a rationale that would guide others in formulating such a system. Thus we examine a wide range of possible BMA systems based on different assumptions, constraints, target levels for representation, and priorities. If one ignores current land ownership and management designations and sets out to represent plant communities in a BMA system based on Calwater planning watersheds (which average roughly 10,000 acres in size), an efficient BMA system requires land in direct proportion to the target level, at least over the range of target levels examined in this study. In other words, it takes roughly 10% of the region to meet a 10% goal, and 25% of the region to meet a 25% goal. The pattern of selected watersheds is very different from the current distribution of parks and wilderness areas, which are concentrated at middle and high elevations in the central and southern portion of the range. Public lands alone are insufficient to create a BMA system that adequately represents all plant community types of the Sierra Nevada. Many of the foothill community types occur almost exclusively on private lands. Terrestrial vertebrates are reasonably well represented in a BMA system selected for plant communities. A BMA system selected for vertebrates alone, however, has little overlap with the one for plant communities. Areas selected by the BMAS model show only a modest amount of overlap with areas selected by other SNEP working groups as focal areas for conserving aquatic biodiversity or late successional/old growth forests. However, the BMAS model can be formulated to favor these areas with little loss of efficiency, especially in the northern Sierra. JF - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options PB - University of California, Centers for Water and Wildlands Resources CY - Davis, California ER - TY - CHAP T1 - Sierran vegetation: A gap analysis T2 - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. KW - gap analysis, California, Sierra Nevada, land management, vegetation AB - Gap analysis assesses the distribution of plant community types and vertebrate species distributions among land classes defined by ownership and levels of protection of biodiversity. Gap analysis helps to identify which plant communities and species might be especially vulnerable to different human activities that can lead to habitat conversion or degradation. This chapter presents a gap analysis of plant community types the Sierra Nevada region, an area of 63,111 km2 (24,368 mi2). Ownership of the region is 37% private, 47% national forests, 10% national parks, 5% Bureau of Land Management, and less than 2% in other public lands. Land ownership and land management patterns contrast sharply between the northern Sierra Nevada versus the central and southern subregions. Parks and reserve lands contribute less than 2% of the northern region versus 27% of the central/southern. We mapped eighty-eight natural plant community types within the region. Sixty-seven types were mapped over areas greater than 25 km2 (9.65 mi2). The ownership profiles of Sierran plant communities systematically reflect the concentration of private lands at lower elevations and of national parks in the central and southern portion of the range. Less than 1% of the foothill woodland zone of the Sierra Nevada is in designated reserves or other areas managed primarily for native biodiversity, and over 95% of the distribution of most foothill community types is available for grazing. Low to middle elevation Sierran forests are not well represented in designated reserves, especially in the northern Sierra Nevada. However, large areas of most of these forest types on U.S. Forest Service lands have been administratively withdrawn from intensive timber management based on current forest plans. Many high-elevation forest and shrubland community types are well represented in parks and ungrazed wilderness areas. Our analysis identifies thirty-two widespread community types whose conservation status warrants concern and twelve types that appear well protected based on their present distributions. JF - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options PB - University of California, Centers for Water and Wildlands Resources CY - Davis, California UR - http://ceres.ca.gov/snep/pubs/web/PDF/VII_C23.PDF ER - TY - CHAP T1 - Sierran vegetation: A gap analysis T2 - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. KW - California KW - gap analysis KW - land management KW - Sierra Nevada KW - vegetation AB - Gap analysis assesses the distribution of plant community types and vertebrate species distributions among land classes defined by ownership and levels of protection of biodiversity. Gap analysis helps to identify which plant communities and species might be especially vulnerable to different human activities that can lead to habitat conversion or degradation. This chapter presents a gap analysis of plant community types the Sierra Nevada region, an area of 63,111 km2 (24,368 mi2). Ownership of the region is 37% private, 47% national forests, 10% national parks, 5% Bureau of Land Management, and less than 2% in other public lands. Land ownership and land management patterns contrast sharply between the northern Sierra Nevada versus the central and southern subregions. Parks and reserve lands contribute less than 2% of the northern region versus 27% of the central/southern. We mapped eighty-eight natural plant community types within the region. Sixty-seven types were mapped over areas greater than 25 km2 (9.65 mi2). The ownership profiles of Sierran plant communities systematically reflect the concentration of private lands at lower elevations and of national parks in the central and southern portion of the range. Less than 1% of the foothill woodland zone of the Sierra Nevada is in designated reserves or other areas managed primarily for native biodiversity, and over 95% of the distribution of most foothill community types is available for grazing. Low to middle elevation Sierran forests are not well represented in designated reserves, especially in the northern Sierra Nevada. However, large areas of most of these forest types on U.S. Forest Service lands have been administratively withdrawn from intensive timber management based on current forest plans. Many high-elevation forest and shrubland community types are well represented in parks and ungrazed wilderness areas. Our analysis identifies thirty-two widespread community types whose conservation status warrants concern and twelve types that appear well protected based on their present distributions. JF - Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options PB - University of California, Centers for Water and Wildlands Resources CY - Davis, California ER - TY - CHAP T1 - A spatial analytical hierarchy for Gap Analysis T2 - Gap Analysis: A Landscape Approach to Biodiversity Planning Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. ED - Scott, J. M. ED - Tear, T. H. ED - Davis, F. W. KW - gap analysis KW - reserve selection KW - scale AB - Representation in the nature reserve system is determined by comparing the distribution of vegetation and vertebrates with that of land ownership and management over a region of interest. Locating potential places to increase representation is typically done by a systematic selection algorithm over a set of spatial units larger than the landscape units of the vegetation map. The landscape is thus the basic spatial unit at which biodiversity data are compiled for Gap Analysis. However, it is only one of four levels of spatial entity that must be explicitly defined in order to complete a Gap Analysis. We refer to these entities as the planning region, the planning unit, the landscape, and the landscape feature. The objective of this paper is to describe a spatial analytical hierarchy for Gap Analysis based on these four entities. Within this broader theme we also present results of a more focused analysis on the effect of planning unit size on the selection of priority conservation areas in southwestern California. JF - Gap Analysis: A Landscape Approach to Biodiversity Planning PB - American Society for Photogrammetry and Remote Sensing CY - Bethesda, MD ER - TY - CHAP T1 - A spatial analytical hierarchy for Gap Analysis T2 - Gap Analysis: A Landscape Approach to Biodiversity Planning Y1 - 1996 A1 - Davis, F. W. A1 - Stoms, D. M. ED - Scott, J. M. ED - Tear, T. H. ED - Davis, F. W. KW - gap analysis, scale, reserve selection AB - Representation in the nature reserve system is determined by comparing the distribution of vegetation and vertebrates with that of land ownership and management over a region of interest. Locating potential places to increase representation is typically done by a systematic selection algorithm over a set of spatial units larger than the landscape units of the vegetation map. The landscape is thus the basic spatial unit at which biodiversity data are compiled for Gap Analysis. However, it is only one of four levels of spatial entity that must be explicitly defined in order to complete a Gap Analysis. We refer to these entities as the planning region, the planning unit, the landscape, and the landscape feature. The objective of this paper is to describe a spatial analytical hierarchy for Gap Analysis based on these four entities. Within this broader theme we also present results of a more focused analysis on the effect of planning unit size on the selection of priority conservation areas in southwestern California. JF - Gap Analysis: A Landscape Approach to Biodiversity Planning PB - American Society for Photogrammetry and Remote Sensing CY - Bethesda, MD ER - TY - JOUR T1 - Validating large-area land cover databases with maplets JF - Geocarto International Y1 - 1996 A1 - Stoms, D. M. KW - gap analysis KW - map accuracy assessment KW - maplet AB - Point sampling methods traditionally used for assessing accuracy of small-area thematic maps are less suitable for large-area, lower resolution maps. Maplets, or detailed maps of small areas, are proposed here as an alternative source of independent reference data for accuracy assessment. As a land cover census instead of a sparse sample of points, maplets can provide information on the composition, heterogeneity, and accuracy of individual map units, on boundary locational accuracy, and the spatial pattern of errors in the large-area map. The techniques is illustrated by a case study for a wildlife habitat map of southern California, USA. Overall agreement between the maplet and the large-are map was 63%. However, the total area of map units in which the label agreed with the majority maplet class was 84%. This result suggests that much of the "error" was actually generalization rather than misclassification. VL - 11 ER - TY - CHAP T1 - Biodiversity in the Southwestern California Region T2 - Our Living Resources: A Report to the Nation on the Distribution, Abundance, and Health of U. S. Plants, Animals, and Ecosystems Y1 - 1995 A1 - Stoms, D. M. A1 - Davis, F. W. JF - Our Living Resources: A Report to the Nation on the Distribution, Abundance, and Health of U. S. Plants, Animals, and Ecosystems PB - USDI, National Biological Service CY - Washington, D. C. ER - TY - CHAP T1 - Biodiversity in the Southwestern California Region T2 - Our Living Resources: A Report to the Nation on the Distribution, Abundance, and Health of U. S. Plants, Animals, and Ecosystems Y1 - 1995 A1 - Stoms, D. M. A1 - Davis, F. W. JF - Our Living Resources: A Report to the Nation on the Distribution, Abundance, and Health of U. S. Plants, Animals, and Ecosystems PB - USDI, National Biological Service CY - Washington, D. C. ER - TY - JOUR T1 - Gap analysis of the actual vegetation of California: 1. The Southwestern Region JF - Madrono Y1 - 1995 A1 - Davis, F. W. A1 - Stine, P. A. A1 - Stoms, D. M. A1 - Borchert, M. I. A1 - Hollander, A. D. KW - California KW - gap analysis KW - vegetation AB - Gap Analysis is a method of conservation risk assessment that evaluates the protection status of plant communities, animal species and vertebrate species richness by overlay of biological distribution data on a map of existing biological reserves. The National Biological Survey has undertaken a national Gap Analysis that is being conducted by individual states but that will eventually produce regional and national assessments. Given California's size and complexity, we are conducting separate Gap Analyses for each of the state's 10 ecological regions, as delineated in The Jepson Manual. Here we summarize our findings on the distribution of plant communities and dominant plant species in the Southwestern Region of California, exclusive of the Channel Islands. We tabulate and discuss regional distribution patterns, management status and patterns of land ownership for 76 dominant woody species and 62 natural communities. Nineteen of 62 mapped communities appear to be at risk, as determined by their poor representation in existing reserves, parks or wilderness areas. Communities restricted largely to the lower elevations, such as non-native grasslands and coastal sage scrub types, are clearly at considerable risk. A majority of the lands at these elevations have already been converted to agricultural or urban uses and most of the remaining lands are threatened with future urbanization. Areas that appear to be of highest priority for conservation action based on agreement between our analysis and a recent assessment by The Nature Conservancy include the Santa Margarita River, San Mateo Creek, Miramar Mesa, Santa Clara floodplain near Fillmore, Sespe and Piru Canyons, and Tejon Pass. VL - 42 ER - TY - JOUR T1 - Distribution and conservation status of coastal sage scrub in southwestern California JF - Journal of Vegetation Science Y1 - 1994 A1 - Davis, F. W. A1 - Stine, P. A. A1 - Stoms, D. M. KW - gap analysis KW - information analyis KW - vegetation classification AB - A landscape-based characterization of vegetation has been developed for southwestern California using satellite imagery, air photos, existing vegetation maps, and field data. Distribution maps of nine dominant coastal scrub species and 13 species assemblages that were identified by divisive information analysis have been analyzed to quantify spatial patterns of species co-occurrence. Three general distribution patterns are identified that suggest the Diegan, Venturan and Riversidian Associations identified by other workers. Vegetation data have also been related to land ownership and management to assess the conservation status of upland plant communities. A large proportion of the mapped distribution of species and vegetation types is on private land, and several taxa show less than 4% of mapped distribution in nature reserves. The analysis highlights the need to extend current conservation planning efforts into the northern part of the region to encompass areas where Salvia leucophylla is a frequent community dominant. VL - 5 UR - ://A1994PX87300011 ER - TY - JOUR T1 - Effects of habitat map generalization in biodiversity assessment - Response JF - Photogrammetric Engineering and Remote Sensing Y1 - 1994 A1 - Stoms, D. M. VL - 60 ER - TY - CHAP T1 - Hierarchical representation of species distributions using maps, images, and sighting data T2 - Mapping the Diversity of Nature Y1 - 1994 A1 - Hollander, A. D. A1 - Davis, F. W. A1 - Stoms, D. M. ED - Miller, R. I. KW - data hypercube KW - orange-throated whiptail AB - Geographic Information Systems technology permits the generation of complex representations of species distributions, while most of the data underlying these patterns are coarse. This suggests the importance of structuring such data along axes of differing data extent, tiling schemes, themes, and time, and displaying different representations of distributions, the philosophy being that comparison of multiple representations provides a sense of the actual distribution through convergence of evidence. We present an example using a lizard, the orange-throated whiptail (Cnemidophorus hyperythrus), which is native to southern California. The analysis was hierarchically structured by first mapping overall lizard range limits, then suitable habitats within the range, and then habitats over a local extent. Data sources include a generalized range outline, museum records, and field observations, as well as climate data, vegetation maps, and satellite imagery to serve as associated environmental variables. Comparison of representations resulting from these different data sources makes biases evident, highlights areas of inadequate sampling, and can lead to new inferences about habitat relationships. Finally, we discuss forthcoming improvements in the technology that will facilitate creation and display of families of models. JF - Mapping the Diversity of Nature PB - Chapman and Hall CY - London ER - TY - CHAP T1 - Hierarchical representation of species distributions using maps, images, and sighting data T2 - Mapping the Diversity of Nature Y1 - 1994 A1 - Hollander, A. D. A1 - Davis, F. W. A1 - Stoms, D. M. ED - Miller, R. I. KW - data hypercube, orange-throated whiptail AB - Geographic Information Systems technology permits the generation of complex representations of species distributions, while most of the data underlying these patterns are coarse. This suggests the importance of structuring such data along axes of differing data extent, tiling schemes, themes, and time, and displaying different representations of distributions, the philosophy being that comparison of multiple representations provides a sense of the actual distribution through convergence of evidence. We present an example using a lizard, the orange-throated whiptail (Cnemidophorus hyperythrus), which is native to southern California. The analysis was hierarchically structured by first mapping overall lizard range limits, then suitable habitats within the range, and then habitats over a local extent. Data sources include a generalized range outline, museum records, and field observations, as well as climate data, vegetation maps, and satellite imagery to serve as associated environmental variables. Comparison of representations resulting from these different data sources makes biases evident, highlights areas of inadequate sampling, and can lead to new inferences about habitat relationships. Finally, we discuss forthcoming improvements in the technology that will facilitate creation and display of families of models. JF - Mapping the Diversity of Nature PB - Chapman and Hall CY - London ER - TY - ABST T1 - Pilot Studies for Southern California: Synoptic National Assessment of Comparative Risks to Biological Diversity and Landscape Types Y1 - 1994 A1 - Stoms, D. M. A1 - Davis, F. W. PB - University of California, Santa Barbara ER - TY - RPRT T1 - Pilot Studies for Southern California: Synoptic National Assessment of Comparative Risks to Biological Diversity and Landscape Types Y1 - 1994 A1 - Stoms, D. M. A1 - Davis, F. W. PB - University of California, Santa Barbara CY - Santa Barbara ER - TY - JOUR T1 - Scale dependence of species richness maps JF - The Professional Geographer Y1 - 1994 A1 - Stoms, D. M. KW - scale gap analysis Idaho GIS biodiversity species richness Intermountain Sagebrush ecoregion Rocky Mountains alpha diversity beta diversity gamma diversity AB - Mapping patterns of species richness is a longstanding tradition in biogeography and more recently in conservation planning. This paper describes the effects of sampling unit size on patterns of vertebrate richness across landscapes in the Intermountain Sagebrush and Rocky Mountain Forest ecoregions in Idaho. Variability of richness decreased with increasing size of the spatial sampling units at both sites, with greater overall variability in the forested site. Richness in the sagebrush region was best explained by alpha diversity, whereas beta diversity accounted for more of the variability in richness in the forested site. VL - 46 ER - TY - JOUR T1 - Compiling a digital map of areas managed for biodiversity in California JF - Natural Areas Journal Y1 - 1993 A1 - Beardsley, K. A1 - Stoms, D. M. KW - gap analysis managed areas California AB - To determine how well the biological diversity of a region is protected, one must know the locations of all managed areas and the level of management being provided at each. In this paper we outline some of the problems confronting cartographers in compiling digital maps of managed areas. These problems involve the classification of management levels, selection of a minimum mapping unit, integration of maps from multiple sources, and the maintenance of data on rapidly changing land ownership. We demonstrate how these problems were resolved for a managed areas map for the state of California. Characteristics of an ideal geographic information system (GIS) database of managed areas are also described. The California map is being produced at a scale of 1:100,000 with a minimum mapping unit of 200 ha for uplands and 80 ha for wetlands. Mapping has been completed for the Southwestern California Ecoregion, and the results and lessons learned are reported here. For this 3-million-ha study region, 9.8% of the total land area was classified at the highest level of protection; these managed areas are concentrated in higher elevation areas. Only 12.1% of significant natural areas in the region, as identified by the California Lands and Natural Areas Program, are currently within well-protected areas. VL - 13 ER - TY - JOUR T1 - Geographic analysis of California condor sighting data JF - Conservation Biology Y1 - 1993 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Cogan, C. B. A1 - Painho, M. O. A1 - Duncan, B. W. A1 - Scepan, J. A1 - Scott, J. M. KW - habitat suitability KW - sensitivity analysis AB - Observation and habitat data were compiled and analyzed in conjunction with recovery planning for the endangered California Condor (Gymnogyps californianus). A geographic information system (GIS) was used to provide a quantitative inventory of recent historical Condor habitats, to measure the association of Condor activity patterns and mapped habitat variables, and to examine spatio-temporal changes in the range of the species during its decline. Only five percent of the study area within the historic range is now used for urban or cultivated agricultural purposes. Observations of Condor feeding perching, and nesting were nonrandomly associated with mapped land cover, in agreement with life history information for the species. The precipitous decline in numbers of Condors in this century produced only a small reduction in the limits of the observed species 'range, as individual birds continued to forage over most of the range. Some critical risk factors such as shooting and lead poisoning are difficult to map and bave not been included in the database Besides the applications demonstrated in this case study, GIS can be a valuable tool for recovery planning, in the design of stratified sampling schemes, or for extrapolation of habitat models over unsurveyed regions. We conclude with recommendations from this case study regarding when to consider using GIS and the importance of pilot studies and sensitivity analysis. VL - 7 UR - ://A1993KR98600021 ER - TY - JOUR T1 - A remote sensing research agenda for mapping and monitoring biodiversity JF - International Journal of Remote Sensing Y1 - 1993 A1 - Stoms, D. M. A1 - Estes, J. E. KW - species richness NDVI net primary production AB - There is an urgent need to inventory and monitor indicators of biological diversity, such as species richness. Remotely sensed data provides a means to accomplish part of this task, but there has been no comprehensive scientific framework to guide its effective application. Here we propose a remote sensing research agenda designed to improve the quality and quantity of information available for testing scientific hypotheses, monitoring, and conservation planning. Biodiversity should be more fully incorporated into ongoing earth system science and global change programs, with remote sensing featured as a prominent data acquisition and analysis tool. VL - 14 ER - TY - ABST T1 - Research Plan for Pilot Studies of the Biodiversity Research Consortium Y1 - 1993 A1 - Kiester, A. R. A1 - White, D. A1 - Preston, E. M. A1 - Master, L. L. A1 - Loveland, T. R. A1 - Bradford, D. F. A1 - Csuti, B. A. A1 - O'Connor, R. J. A1 - Davis, F. W. A1 - Stoms, D. M. PB - U. S. Environmental Protection Agency ER - TY - CONF T1 - Beyond the traditional vegetation map towards a biodiversity database T2 - Gis/lis'92 Y1 - 1992 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Stine, P. A. A1 - Borchert, M. JF - Gis/lis'92 PB - American Society for Photogrammetry and Remote Sensing CY - San Jose ER - TY - JOUR T1 - Effects of habitat map generalization in biodiversity assessment JF - Photogrammetric Engineering and Remote Sensing Y1 - 1992 A1 - Stoms, D. M. KW - habitat suitability KW - scale KW - sensitivity analysis KW - species richness AB - Species richness is being mapped as part of an inventory of biological diversity in California (i.e., gap analysis). Species distributions are modeled with a GIS on the basis of maps of each species' preferred habitats. Species richness is then tallied in equal-area sampling units. A GIS sensitivity analysis examined the effects of the level of generalization of the habitat map on the predicted distribution of species richness in the southern Sierra Nevada. As the habitat map was generalized, the number of habitat types mapped within grid cells tended to decrease with a corresponding decline in numbers of species predicted. Further, the ranking of grid cells in order of predicted numbers of species changed dramatically between levels of generalization. Areas predicted to be of greatest conservation value on the basis of species richness may therefore be sensitive to GIS data resolution. VL - 58 UR - ://A1992JV67200007 ER - TY - CONF T1 - Modeling vegetation cover types from a topographic gradient in the southern Sierra Nevada T2 - Gis/lis'92 Y1 - 1992 A1 - Walker, R. E. A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Wagtendonk, J. van JF - Gis/lis'92 PB - American Society for Photogrammetry and Remote Sensing CY - San Jose ER - TY - CONF T1 - Relationships between biological diversity and multitemporal vegetation index data in California T2 - 1992 Annual Meeting of ASPRS/ACSM Y1 - 1992 A1 - Walker, R. E. A1 - Stoms, D. M. A1 - Estes, J. E. A1 - Cayocca, K. D. JF - 1992 Annual Meeting of ASPRS/ACSM PB - American Society for Photogrammetry and Remote Sensing CY - Albuquerque ER - TY - JOUR T1 - Sensitivity of wildlife habitat models to uncertainties in GIS data JF - Photogrammetric Engineering and Remote Sensing Y1 - 1992 A1 - Stoms, D. M. A1 - Davis, F. W. A1 - Cogan, C. B. KW - habitat suitability KW - sensitivity analysis AB - Decision makers need to know the reliability of output products from GIS analysis. For many GIS applications, it is not possible to compare these products to an independent measure of "truth." Sensitivity analysis offers an alternative means of estimating reliability. In this paper, we present a GIS-based statistical procedure for estimating the sensitivity of wildlife habitat models to uncertainties in input data and model assumptions. The approach is demonstrated in an analysis of habitat associations derived from a GIS database for the endangered California condor. Alternative data sets were generated to compare results over a reasonable range of assumptions about several sources of uncertainty. Sensitivity analysis indicated that condor habitat associations are relatively robust, and the results have increased our confidence in our initial findings. Uncertainties and methods described in the paper have general relevance for many GIS applications. VL - 58 UR - ://A1992HX38700006 ER - TY - CONF T1 - Gap analysis of biodiversity in California T2 - Symposium on Biodiversity of Northwestern California Y1 - 1991 A1 - Davis, F. W. A1 - Stoms, D. M. KW - geographic information system, Wildlife-Habitat Relationships System, vegetation mapping AB - Most conservation efforts in California are conducted at local to sub-regional scales, and focus on species or communities of special concern. Currently lacking is an overview of the protection status of species and communities both statewide and in the western U.S. This paper describes a GIS-based Gap Analysis of biodiversity that is part of a national program being coordinated by the U.S. Fish and Wildlife Service. "Gap Analysis" is the evaluation of the protection status of plant communities and vertebrate species by GIS overlay of biological distribution data on a map of biological reserves. The biodiversity assessment for California is using existing digital geographical data sets on land ownership, topography, species ranges and locations of threatened and endangered species. An up-to-date statewide vegetation map is being produced using digital Thematic Mapper (TM) satellite data. The vegetation map is used in conjunction with the California Wildlife Habitat Relationships (WHR) System and digital species range maps to predict potential distributions of native terrestrial vertebrates. Research to date has concentrated on the south coastal region, and has been involved in compiling existing data sets, refining mapping methods and testing the sensitivity of the biodiversity assessment to map scale and minimum mapping unit. A hybrid method of digital image classification and manual image interpretation has been developed that appears promising. Test areas exhibit very different scales of vegetation pattern and different sensitivity to data resolution, implying the need for different minimum mapping units for different physiographic regions of the state. JF - Symposium on Biodiversity of Northwestern California PB - University of California Wildland Resources Center CY - Santa Rosa, California ER - TY - CHAP T1 - An information systems approach to the preservation of biological diversity T2 - GIS Applications in Natural Resources Y1 - 1991 A1 - Scott, J. M. A1 - Estes, J. E. A1 - Scepan, J. A1 - Davis, F. W. A1 - Stoms, D. M. ED - Heit, M. ED - Shortreid, A. JF - GIS Applications in Natural Resources PB - GIS World, Inc. CY - Ft. Collins, Colorado ER - TY - CHAP T1 - An information systems approach to the preservation of biological diversity T2 - GIS Applications in Natural Resources Y1 - 1991 A1 - Scott, J. M. A1 - Estes, J. E. A1 - Scepan, J. A1 - Davis, F. W. A1 - Stoms, D. M. ED - Heit, M. ED - Shortreid, A. JF - GIS Applications in Natural Resources PB - GIS World, Inc. CY - Ft. Collins, Colorado ER - TY - THES T1 - Mapping and monitoring regional patterns of species richness from geographic information Y1 - 1991 A1 - Stoms, D. M. AB - Biological diversity has become a major scientific and pol- itical issue, producing an urgent need for inventory and monitoring programs. Remote sensing provides tools to satisfy part of this need, but there has been no scientific framework for guiding its application in biodiversity as- sessments. A research agenda is proposed to expand our knowledge of the role remote sensing might play in providing improved information on the spatial distribution of species richness and its ecological determinants, and the response of these ecological factors to global change. Many physical and biological factors that are correlated with species richness have been mapped with remote sensing, including landscape geometry, primary productivity, and evapotran- spiration. Additional research is required to apply remote sensing methods to the assessment of biodiversity in the context of earth system science and global change programs. Sensitivity of maps of predicted species richness to spatial scale and habitat map generalization and accuracy were exam- ined by means of a geographic information system (GIS) sen- sitivity analysis. Wildlife-habitat relationships (WHR) models were integrated with a map of habitats to predict species number within uniform grid cells for two distinct ecoregions in Idaho. Patterns of richness varied unpredict- ably with size of the spatial sampling units because of the complex interaction of factors that affect richness. For statewide Gap Analysis, a range of grid sizes between 10- 100,000 ha are recommended for the Rocky Mountain Forest ecoregion and 10-60,000 ha for the Intermountain Sagebrush ecoregion. Contiguous, non-overlapping grids provide ade- quate sampling density. Another GIS sensitivity analysis ascertained the effects of the level of generalization (minimum mapping unit) and accu- racy of the habitat map on the predicted distribution of richness in the southern Sierra Nevada, California. Predicted richness declines monotonically as the habitat map is generalized, due to reduction in the number of habitat types mapped in a quadrat. Misclassification had the oppo- site effect of predicting more species than the baseline model. Both factors produced changes in the grid cells predicted as having the most species. It is expected that these effects diminish as sampling unit size increases. ER - TY - RPRT T1 - The Use of Vegetation Maps and Geographic Information Systems for Assessing Conifer Lands in California Y1 - 1991 A1 - Goodchild, M. F. A1 - Davis, F. W. A1 - Painho, M. A1 - Stoms, D. M. PB - NCGIA CY - Santa Barbara SN - 91-23 UR - "http://elib.cs.berkeley.edu/cgi-bin/doc_home?elib_id=1732" ER - TY - ABST T1 - The Use of Vegetation Maps and Geographic Information Systems for Assessing Conifer Lands in California Y1 - 1991 A1 - Goodchild, M. F. A1 - Davis, F. W. A1 - Painho, M. A1 - Stoms, D. M. PB - NCGIA ER - TY - JOUR T1 - An information systems approach to the preservation of biological diversity JF - International Journal of Geographical Information Systems Y1 - 1990 A1 - Davis, F. W. A1 - Stoms, D. M. A1 - Estes, J. E. A1 - Scepan, J. A1 - Scott, J. M. VL - 4 ER -